AB0806 THE LONG-TERM COURSE OF THE HEALTH ASSESSMENT QUESTIONNAIRE IN PATIENTS WITH SYSTEMIC SCLEROSIS
Authors: S. Liem, S. A. Bergstra, J. Ciaffi, C. Van der Meulen, D. Ueckert, R. Schriemer, T. Huizinga, T. P. M. Vliet Vlieland, J. De Vries-Bouwstra
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Functional disability in patients with systemic sclerosis (SSc) greatly influences quality of life. The Health Assessment Questionnaire-Disability Index (HAQ-DI) is an important outcome reflecting functional disability, but knowledge on its course over time in SS) is scarce. <h3>Objectives</h3> To describe the long-term course of functional disability in SSc patients, most importantly to investigate which patients have a worsening functional ability, and investigate its associations with disease characteristics. <h3>Methods</h3> SSc patients, fulfilling the ACR/EULAR 2013 criteria, were included from the Leiden CCISS cohort with annual assessments including the Scleroderma HAQ. The Scleroderma HAQ consists of the HAQ-DI (range: 0 [no difficulties] to 3 [maximum difficulties]) and five SSc-related VAS scores: Raynaud's Phenomenon, digital ulcers, gastrointestinal, pulmonary and general disease burden (range: 0 to 100). The HAQ-DI course was evaluated over the total follow-up (baseline to last available HAQ-DI) and between yearly visits. Based on a minimal clinical important difference of 0.22, patients were categorized into worsening, stable, or improvement. Baseline SSc characteristics were compared between patients with a worsening or improvement of the HAQ-DI using logistic regression. The change of the HAQ-DI and the SSc-related VAS scores over time was evaluated with linear mixed models. <h3>Results</h3> 517 SSc-patients were included (Table 1). The median follow-up duration was 7 years (IQR:4; 9). The mean baseline HAQ was 0.77 (SD:0.65). On group level, the HAQ-DI increased annually with 0.019 (95% CI:0.011; 0.027). Patients ≥65 years (β 0.27, 95% CI: 0.1; 0.4) and patients who died/were physically not able to come during follow-up (β 0.34, 95% CI: 0.2; 0.5) had a significantly higher HAQ-DI over time than respectively patients younger than 65 years old and patients who did not die (Figure 1). Between baseline and the last follow-up, the proportions of patients with a worsening, stable or improved HAQ-DI were 35%, 42% and 23%, respectively. Logistic regressions, adjusted for age, sex and disease duration, revealed that, at baseline, the use of immunosuppressive medication (OR: 0.5, 95% CI: 0.3; 0.9) and gastrointestinal involvement (OR: 0.6, 95% CI: 0.4; 0.9) decreased the chance of a worsening overall HAQ-DI course, whereas presence of anti-centromere autoantibodies (OR: 1.4, 95% CI: 0.8; 2.3) and pulmonary arterial hypertension (OR: 2.3, 95% CI: 0.3; 20.8) increased this. For all the VAS scores, the β of the longitudinal course for the total group was stable. Over time, most importantly, patients who died/were physically not able to come during follow-up had a 18.8 point higher pulmonary VAS (95% CI: 12.9; 24.8) and a 13.3 higher general burden of SSc VAS (95% CI: 6.5; 20.2) compared to patients who survived. <h3>Conclusion</h3> Over time, the average course of the HAQ-DI is stable in SSc-patients, but individual trajectories vary, with worsening occurring in one third. Importantly, use of immunosuppressives decreased the chance of worsening while presence of anti-centromere antibodies increases the chance of worsening. <h3>Disclosure of Interests</h3> Sophie Liem: None declared, Sytske Anne Bergstra: None declared, Jacopo Ciaffi: None declared, Coen van der Meulen: None declared, David Ueckert: None declared, Rita Schriemer: None declared, Thomas Huizinga: None declared, T.P.M. Vliet Vlieland: None declared, Jeska de Vries-Bouwstra Grant/research support from: JVB received research grants from Roche, Galapagos and Janssen and consulting fees from Abbvie, Janssen and Boehringer Ingelheim. All was paid to her institution.